为了培养本科生的动手实践技能,引导学生积极参与科研活动,建设一个高质量的开放实验教学平台是十分必要的.本文设计了一个家电智能化科研的实验平台.平台含有多层次的实验内容,可服务于线上线下混合教学和开放性实验教学.该实验平台对激发学生的学习潜力和促进专业能力的个性化发展有一定的积极作用.
本文从STM32单片机的教学入手,对物联网工程专业学生知识体系构建能力的培养方法进行了探讨.通过分析物联网工程专业的特点以及传统教学中学生构建知识体系结构时存在的问题,提出了由易到难、项目引领、就业驱动、以点带面的系统性思维培养模式,旨在提高学生构建专业知识体系的能力.
根据物联网与传感技术课程的特点和应用型人才培养的思路,本文阐述了一种面向工作过程的项目引导式教学方法,按照技术工程师成长的过程来重构和组织教学内容,改变原来的按照知识体系结构去组织教学内容的顺序,让学生在日常的学习中充分发挥自己的主观能动性,主动学习专业知识,实现应用型人才的培养目标.
根据AISG2.0协议对时分复用塔顶放大器(Time Division Duplex-Tower Mounted Amplifier,TDD-TMA)的控制性能要求,提出了一种TMA嵌入式控制单元设计方案.设计了基于对数放大器和射频开关的OOK通信模块,有效解决了发送信号绕回到接收端的问题.设计了基于电流负反馈的可配置式电流告警电路,实现了告警电流的精确控制.给出了AISG协议栈和TMA故障检测与处理模块的软件实现方法.测试结果表明,该设计方案通信及控制性能符合AISG协议要求,状态监控功能完善,且当AISG通信故障时具备自动切换到电流告警模式的功能.
Aiming at the low efficiency and complicated operation problems commonly existing in the current installation and debugging tools of antenna line device ( ALD) , a portable ALD control equipment design scheme conforming to AISG protocol was proposed. A demodulation method based on the logarithmic amplifier was employed to realize the OOK communication circuit with adjustable receiving sensitivity. The device scanning method of AISG protocol was analyzed, and a quaternary tree scanning algorithm for distinguishing the ALD device type was designed, which could realize the rapid identification of ALD devices with different types on the AISG bus. The results show that the proposed design scheme accords with the specification requirement of AISG protocol, exhibits the impeccable control function, and also has the advantages of good protocol compatibility and high device scanning speed.
According to the communication and control performance requirement of Time Division Long Term Evolution ( TD-LTE) network' s Time Division Duplex( TDD) work mode for tower mounted ampli-fier ( TMA) ,a controller design scheme is provided which conforms to Antenna Interface Standard Group ( AISG) protocol. Circulator and high power radio frequency( RF) switch are jointly employed to build the transceiver module,which improves the isolation between uplink and downlink and also avoids the closed loop self-excitation. A demodulation method based on logarithmic amplifier is used to realize the OOK communication circuit with adjustable demodulation sensitivity. TMA state detection and fault handling methods are designed through synchronous measurement of its working current during uplink slot to improve the efficiency of fault exploration and recovery. Test results show that the presented design scheme primely meets the requirement of AISG protocol,the state monitoring function is perfect,alarm raising way is reson-able,and it also features auto-recovery function under non- permanent failure.
单片机是嵌入式及物联网专业的一门专业基础课,其教学效果将直接影响学生的动手能力和专业自信.由于该课程知识点多、应用场景繁杂等特点,学生学习难度较大,教学效果不理想.针对该教学现状,分析了单片机课程教学及当代学生学习的特点,该文阐述了将工程实践案例和微课程相结合的单片机课程教学改革模式,以工程案例突出知识运用,通过微课加强基础知识的学习,通过考核方式改革和学科竞赛强化能力培养.实践证明,该方法能够有效提升学生的学习兴趣,教学效果明显改善.
In order to add the solar battery charging device in the electric vehicle and realize the maxim power point track-ing (MPPT),a specialized solar battery charging control system was designed and implemented. The application background and design requirement of this industry are introduced briefly. The hardware design scheme of the system is described in detail in the aspects of the system structure,power supply topology,boosted circuit and power detection. The software design thought is introduced in the aspects of high-efficiency data acquisition scheme and MPPT algorithm. The schemes of the efficiency test and MPPT effect test are given. The practical application results show that the design scheme has high tracking efficiency,high cost performance,and stable and reliable long-term operation.
With the rapid popularization of mobile phone and the development of wireless communication technology,the optimization task of wireless network becomes increasing heavy.Antenna line devices (ALDs) which conform to AISG2.0 protocol are widely used.To satisfy the installment and maintenance of vast ALDs,portable ALD control equipment was designed.The application background was analyzed first,aud then system hardware scheme was discussed in the following aspects:battery management,communication interface and over current protection.The software implement method of AISG protocol stack and battery manage system were investigated in details.At last,protocol interoperation test and energy consumption measurement were conducted.Test and application results show that the proposed design preliminarily meets the electronic and protocol integrity requirement of AISG2.0,and show good performance in operation efficiency and its outstanding duration time under energy consumption operation.
According to AISG2.0 technical requirement on Multi-Band remote electronic tilting antenna (MRET) on state detection,modifying tilt angle and alarm reporting,embedded control unit of MRET conforming to AISG2.0 was designed.The hardware system diagram was given first,then the communication interface,inrush current suppression circuit and tilt angle driver were discussed.In software module,the idea of protocol stack and tilt angle detection and control function was proposed,and the design of firmware download and activation was provided in details.Application results show that the proposed design conforms to AISG2.0 in the electronic performance and protocol integrity,and features its good compatibility and long-term stability.
The design scheme of embedded controller in MRETA (multi-band remote electronic tilting antenna) which meets AISG2.0 requirement was present.According to the physical layer requirement of AISG2.0,one OOK (on-off keying) modem circuit which is composed of discrete component was present,and the working principle of how to modify its receiving sensitivity and output power were discussed in details.The feature of MRETA's inrush current was analyzed,and one inrush current suppression circuit was designed,which can meet the corresponding requirement even when the power was frequently switched on and off.The hardware design idea of MRETA tilt angle control module with position feedback was proposed.The software implement methods of protocol stack and tilt angle control function were investigated.Finally,hardware performance and IOT (interoperability test) result were present.Test and application results show that this proposed design scheme sound conforms to AISG2.0 in the electronic performance and protocol integrity,and features its good interoperation compatibility and long-term reliability.
According to AISG2. 0 technical requirement for Tower Mounted Amplifier(TMA) with standing-wave monitoring function on state detection,fault report and data communication,the design and realiza-tion method are presented. In the hardware aspect,system diagram is given first,and then the on-off ke-ying( OOK ) module, configurable current alarm circuit, inrush current suppression and standing-wave measurement circuit are investigated. Implementation method of AISG protocol stack and low noise ampli-fier( LNA) and standing wave fault detection flow are discussed in detail. Test of electrical performance, monitoring function and protocol integrity shows that the present design scheme primely matches the re-quirement of AISG2. 0,and interoperability test with major base station system supplier has been success-fully accomplished.
分析嵌入式及物联网方向的知识结构和学生学习行为的特点,阐述嵌入式工程实践课程在专业知识体系中的地位和作用,介绍嵌入式工程实践课程建设方案、实验平台设计理念和考核方式.
In view of the problems such as high cost,low efficiency,low quality of shooting and limited to the plane, the implementation scheme of 3D automatic imaging system is given.It uses the serial communication technology as the main research means,breaking through of the traditional photography,and it makes product photography simple and panoramic from now on. They only need to equipped with a computer and Single Lens Reflex camera, the system control Single Lens Reflex camera and intelligent rotating platform for many angles shooting through 3D automatic imaging software,then can synthesize the html5 product that is 360 degrees display animation in a few minutes.And made out of the 360 degree display animation can be uploaded to the website and online shop and the sample of the 360 degrees panoramic display effect can be sent to customers. As long as the customer points to open the 360 degrees panoramic display animation; they can accurately view the product's different angles and details. It greatly improves the user experience, so as to increase product sales.
基于嵌入式人才的能力结构分析,提出嵌入式系统教学体系的构建思路,包括嵌入式系统相关核心课程和教学内容设置、针对不同培养目标的课程组合方案以及嵌入式实践教学体系设计.
以彩涂钢板生产工艺为背景,阐述了基于S7-400PLC和6SE70逆变器的交流调速传动控制系统的设计.介绍了彩涂钢板生产线中各工段的工作过程和控制要求,重点研究了Profibus网络通信与网络配置、公共直流母线供电及制动方案以及矢量控制在该调速系统中的应用.实际应用证明,该系统运行稳定、可靠,维护量小,控制精度高,对类似系统的设计与运行调试具有一定的参考价值.
An error control coding method is proposed to improve the reliability of serial data transmission for the display information of a LED large screen remote communication system.Considering the difference of the hardware basis and the implementation requirements between a transmitter and a receiver,a parallel algorithm structure is presented at the information transmitter,and the generating coding matrix is deduced to improve the real time performance of the coding algorithm.Moreover,a dual clock serial circulation decoding structure is presented at the information receiver,in which the high-speed clock after serial syndrome computation is used to correct the error bit to allow the long codeword to obtain a low hardware overhead and real time processing ability.Practice and theoretical analysis shows that the designed scheme can accomplish a high effective coding in efficiency of 98.2%,and can reduce the bit error rate effectively at least 1 order of magnitude in the application.The scheme can achieve high efficient serial transmission of display information.
To realize the sensorless control of brushless DC motor(BLDCM),a BLDCM control solution was designed to detect rotor position by directly detecting the back electronmotive force(EMF) of idle winding.The detecting principle of back EMF and deficiency of routine techniques were highlighted,and a method was elaborated which directly detect the back EMF by ADC during PWM OM period and improve the zero-crossing testing accuracy by software compensation.The BLDCM loop-closed switch operation and starting-up strategy were discussed.The experimental results indicate that the system is accurate in switching,stable and realiable in high-speed running with a good engineering practice reference.
This paper proposes a method of classification and representations for touch gestures based on meta-action and defines a set of stroke touch gestures for Human-Machine Interaction(HMI).A method of touch gesture training and recognition is presented based on RBF neural network.Experiment results show that the proposed method is reliable and efficient for the training and recognition of touch gestures,and can provide a more natural and intuitive human-machine interaction for devices with touch screen.
首先根据AISG通信特点,提出基于二叉扫描树的ALD扫描算法,该算法通过引入冲突队列,对扫描过程中发生的冲突进行分解并生成新的扫描码.然后在分析二叉扫描树特点的基础上,提出自适应二叉树ALD扫描算法,该算法能够根据扫描过程中的一些先验结果跳过部分冲突节点,有效减少扫描过程中的冲突次数,提高扫描效率.实际开发的电调天线控制系统采用自适应二叉树扫描算法,证明该算法具有较好的适用性,可以快速准确地扫描、识别不同厂商的各种ALD设备.